Add experimental support for paragraphs

@jhuhta , we also noticed the clobering of our node translations and media translations as well as term translations.

There is a 3 line fix, I wish the maintainers of this project would please pay attention.

The module is not working in its current form, due in part to this change record → and to an issue with the "translation" field that is currently being worked on 🐛 content_translation_entity_extra_field_info is obsolete Needs work

I came across another problem for which I created another issue 🐛 MergeRemoteStructure calls ParagraphsWidget::isApplicable for all field types indiscriminately Active

Attached is an attempt to address those problems (it currently requires clearing the cache, to take the new hooks into account).

Finally the bug in #3070595-13: Add experimental support for paragraphs → is linked to the fact that the module stores the widget being used by the paragraph field in a "conflictWidget" property, on the field item list object which accidentally (I think) calls \Drupal\Core\Field\FieldItemListInterface::__set() and causes it to be added to the field's value. Which in turns makes the validation fail upon submitting the entity form.
I am not sure of the best way to fix this and obtain the list of fields actually being displayed by the paragraph widget.